Charging Multiple Vehicle Batteries

[special_dx]

Hi All

I am looking for a controller to trickle charge up to 4 small AGM batteries on seperate channels for my stored motorcycles, they are all in the 7-12Ah range and I would also like to run some 12v lighting.

I need suggestions for a controller that keeps the batteries in good condition and is suitable for long term connection without use of the batteries. prior to moving here, I used a couple of Optimate type chargers and ideally I would like the same standard of conditioning/optimization.

It had struck me I may need a controller and seperate multi channel charger, suggestions most welcome.

Would I be right to think that I should look to establish a suitable controller as the start point, taking into account my requirements, then look for a panel to match?

Thanks
Matt

[Sunking]

Hi All

I am looking for a controller to trickle charge up to 4 small AGM batteries ....

on seperate channels for my stored motorcycles, they are all in the 7-12Ah range and I would also like to run some 12v lighting.

I need suggestions for a controller that keeps the batteries in good condition and is suitable for long term connection without use of the batteries.

Well things don't quite work that way, but you can do what you want, it just does not work quite the way you are suggesting unless you have the $$$$ to make a lot of individual systems.

You can group several batteries together to a single charge controller and solar panel to trickel charge the AGM batteries no problem at all. But if you want SEPERATE CAHNNELS requires seperate systems for each battery.

I would suggest 2 systems one to T charge your long term batteriy storage, and another small systems with deep cycle battery for lights. Or just one system using the AGM batteries for batteries and lighting in cycle service. It just takes a little larger solar panel and CC, but doable and less expensive.

[Mike90250]

Another way to keep batteries topped off, is to use a simple dumb charger, and plug it into a wall timer, to run 1 hour a week.
A 3A charger should maintain 4 of your AGM's in parallel just fine. Or get 4, 1 A motorcycle maintainers, and a power strip, and plug the strip into the timer.

AGM are very touchy about being over charged, so read the battery specs and the charger specs well.

[Sunking]

AGM are very touchy about being over charged, so read the battery specs and the charger specs well.

Mike FWIW AGM or any FLA battery can be float cherged till the lights go out so to speak with no problem. Just about every Telco and POCO use AGM's with Float chargers. Trick as with any FLA is the right FLOAT voltage.

[special_dx]

Thanks All

I really want to be able to charge the bikes on pigtails permanently connected to each bike's battery. I have all but one battery in my porch at the moment on mains powered Optimate chargers, the remaining battery is on a bike with a solar dash charger modified to connect to the Optimate fused pigtail, the other bikes have ancillaries like alarms that draw too much power for this approach in the winter months.

I sometimes run a mains cable across to the garage and set up the Optimates inside with the bikes, but often find there is not much room for error as the smaller batteries can drop too low in 2 weeks. The optimate then sees the alarm draw as a fault and I have to remove the battery to get the chargers to work. The resilience of the 12Ah generic/Chinese AGM battery appears disproportionately better than the 7 and 8Ah AGM units, which are all newer and branded (Lucas, Varta, Yuasa), it must be how the technology scales.

I have seen an 80W 12v controller with 3 or 4 seperate 12v outputs, but I am not sure it will be as good at prolonging AGM battery life as the Opimates, it is a 'Juta' branded item, the model number is CMP12. I think this could do a battery for lighting and the bikes, but might need additional DIY circuitry.

I want to get the lighting done as I am using a 12v, 8W flourescent tube (inspection lamp) on one of the AGM pigtails and some 3W LED flashlights for directional stuff. I'm a bit of a flashlight geek, but I see the benefits of CFL over LED for some purposes.

Matt

[Sunking]

The resilience of the 12Ah generic/Chinese AGM battery appears disproportionately better than the 7 and 8Ah AGM units, which are all newer and branded (Lucas, Varta, Yuasa), it must be how the technology scales.

Well Chinese are not known for their quality. My only experience with communist batteries are Thundersky LFP batteries, and they are no where near as good as say A123 Systems or Panasonic. However i suspect what you are noticing is the 12 AH vs the 7 & 8 AH capacity. That is quite a bit of difference of 71 and 50% more capacity

I have seen an 80W 12v controller with 3 or 4 seperate 12v outputs, but I am not sure it will be as good at prolonging AGM battery life as the Opimates, it is a 'Juta' branded item, the model number is CMP12. I think this could do a battery for lighting and the bikes, but might need additional DIY circuitry.

Matt i had a look at the Juta CMP12 and it does not have 3 or 4 battery outputs, just one like any CC I have ever seen.

It has 2 outputs, one for the battery, and one for a load device like a radio. The load output is there to be used with a Low Voltage Disconnect (LVD) and built in fault current protection by using a fuse or breaker. So when the battery voltage gets too low it will cutoff the load device to prevent over discharging the battery, and will not reconnect until the battery is recharged.

[solarbikeaustralia]

Hybrid System to Solar Charge an Electric Bicycle Video

There are a few different ways to solar charge an electric bicycle but
this is probably my favourite system; I can use one 48V panel through
a custom regulator to go straight to a lithium ion battery or else I
can use the same panel to charge a battery bank to store the energy
and then use an inverter and the normal battery charger for the bike
battery. I've made a short video to show how to do this and put it on
youtube. You can also access it through my Solar Bike website -
solarbike.com.au

[wbread99]

I agree with your posts, but will go 1 further.... 12 bikes in a stand alone trailer

So Ive been surfing for this subject post for ever. This is the closest I've come to my situation.

Here in Montana, I teach motorcycle safety, and our organization has several trailers located across the state with 12-14 bikes in each one.

Our teaching season is April to Sept which leaves our 200 or so motorcycles to sit in trailers for the (very) cold 6 months of the year.

Each year, the program spends a substantial amount of money on batteries. Mostly on highly sulfated and just plain dead batts in the spring.

Using my very primitive DIY solar experience here at the house, I proposed to our program director that on a prototype trailer, we could use a solar panel and some sort of power distribution panel to deliver trickle power to all 12 motorcycles in the trailer. Imagine 12 bikes in a trailer parked on a flightline with no access to commercial power. It was a primitive idea.

Ive come to realize that any centralized connection between all 12 batteries (power distribution point) would have all 12 batteries trying to equalize the collective amperage between themselves.

I think something, be it a diode or an individual charge controller (times 12) would ensure batteries do not back feet each other.

Am I missing something? Can a guy with an idea to keep a trailer full of 12 motorcycles alive through the winter do it for the price we pay for batteries each year?

Thanks in advance!

[Sunking]

I think something, be it a diode or an individual charge controller (times 12) would ensure batteries do not back feet each other.

Am I missing something? Can a guy with an idea to keep a trailer full of 12 motorcycles alive through the winter do it for the price we pay for batteries each year?

Does not have to be that complicated. Assuming the bikes are stored with the batteries fully charged from use, all you need is enough power to keep them in float. Something like a 200 watt panel which is capable of delivering about 1- amp to each battery.

The way to eliminate large EQ currents is by proper wire selection using something small and let the resistance of the wire to keep EQ currents to tolerable levels. Once the batteries are EQ, then the charge current will be equal among all of them and self regulate.

Just use a KISS Engineering approach. (Keep It Simple Stupid)

[wbread99]

[QUOTE= Just use a KISS Engineering approach. (Keep It Simple Stupid)[/QUOTE]

Old military term to tell the peeps to not read into what we were asking of them.

thanks for quick reply.

Problem (maybe) is the bike batts would never be at the same amperage. Of 12 allowed, we might only teach 8-10. Our job to rotate bikes.... got it.

My thoughts from my 12VDC flood light installation in the back yard is the longer the cord, the less the current to the light. Given that, should I cut all 12 lengths the same length even though the closes bikes to the power distribute would be much closer?

Thanks in advance. I love this stuff.

[Sunking]

Problem (maybe) is the bike batts would never be at the same amperage. Of 12 allowed, we might only teach 8-10. Our job to rotate bikes.... got it.

No problem with different size batteries when they are just being floated in storage. If cycled it is a problem, but not for storage.

[PNjunction]

Battery Minders (not Battery-Tender!) will do what you want in either their AC charger / maintainers, or their solar charge controllers. They have intelligent Y-cables that isolate and charge each battery individually from single chargers or solar controllers designed to handle multiple batteries.

Their solar controllers are the SCCxxx models, and the intelligent y-adapter splitters like the 210AY model can be seen in their accessories section.

They are well built, (although I don't have experience with the charge controllers, although the big SCC180 might be in my future for testing), come with good documentation and have nothing to hide. While for many of us the "full time desulphation" feature might be a turn off, I've found them to be excellent chargers on their own, and one can just ignore that desulphation claim if they want. Accurate voltages, good build-quality, full docs, and emphasis on temperature compensation are a big plus.

I'd definitely inquire / look into them for both your ac and solar bike charging projects. Seriously.